body {
  font-size: 100%; }

#header {
  width: 100%;
  position: relative; }
  #header .mainPic {
    width: 100%;
    display: block; }
  #header .btn_play {
    position: absolute;
    top: 4.5rem;
    width: 3.36rem;
    height: 1.11rem;
    left: 50%;
    margin-left: -1.68rem;
    cursor: pointer; }
  #header .code {
    position: absolute;
    bottom: 0px;
    right: 0px;
    width: 2.14rem;
    height: 2.5rem; }
  #header .mask {
    width: 100%;
    height: 100%;
    background: #282829;
    position: fixed;
    left: 0px;
    top: 0px;
    opacity: 0.6;
    z-index: 2; }
  #header .video {
    position: fixed;
    top: 50%;
    width: 100%;
    margin-top: -35%;
    z-index: 3; }
    #header .video video {
      width: 100%;
      z-index: 4; }
    #header .video .imgVideo {
      position: absolute;
      left: 0px;
      top: 0px;
      width: 100%;
      z-index: 5; }

.dn {
  display: none; }
